There are increasing awareness and concern about the radiological impact of dust from soils along the roadways on petty traders and commuters in major commercial areas of Ghana. Soils in such commercial areas can be contaminated by road dust that could alter their radiological characteristics. This is because of the general exposure of road dust to environmental elements such as industrial and urban activities and also exhaust fumes from the vehicles. In the present study, 52 surface soil samples were collected along six roadways in the Ketu South District of the Volta Region, Ghana. The study area is one of the high commercial activities and consequently high traffic density. The measures of the specific activity concentration of²³⁸U,²³²Th, and⁴⁰K in the samples were taken using high-purity germanium (HPGe) gamma-ray spectrometry. The results were evaluated to assess the radiological impact due to roadside soil in the area. The activity concentration in the samples ranged from 74.62 to 156.3 Bq/kg for²³⁸U, with an average of 112.4 Bq/kg. The activity concentrations of²³²Th ranged from 6.5 to 29.0 Bq/kg, with an average of 14.6 Bq/kg and that of⁴⁰K ranged from 83.76 to 224.27 Bq/kg with an average of 141.02 Bq/kg. The results were used to estimate the radiological parameters of the study soils. The levels of radium equivalent activity (Ra_eq), absorbed dose rate (D), and annual effective dose (E) in them were lower than the recommended or safe limits proposed by international bodies such as UNSCEAR (2000) or ICRP (1991). These findings indicated that soils in the studied area had the normal levels of radiation and were therefore radiologically safe.

The terrestrial gamma radiation levels and associated dose rates were estimated at 120 different sites with 12 soil samples in the southern hilly regions of Manipur, India, consisting of Churachandpur and Chandel district, by using NaI (Tl) scintillator-based Micro-R survey meter and high-purity germanium detector. The observed annual effective dose in this study area ranges from 0.37 to 1.51 mSv/y, with a mean value of 0.85 ± 0.16 mSv/y. Whereas Churachandpur and Chandel districts showed a mean value of 0.88 ± 0.18 (ranges: 0.67 to 1.51) mSv/y and 0.83 ± 0.14 (ranges: 0.37–1.24) mSv/y, respectively. This southern region of Manipur shows slightly higher values of annual effective dose as compared with the earlier reported value of about 0.7 mSv/y for the central valley region of Manipur, and world average value of about 0.4 mSv/y, reported by United Nations Scientific Committee on the Effects of Atomic Radiation (2000). The soil analysis for²²⁶Ra,²³²Th, and⁴⁰K of this area gives an average activity concentration of 44.3 (ranges: 23.8–78.6) Bq/kg, 169.1 (ranges: 83.6–305.1) Bq/kg, and 1489.1 (ranges: 752.5–2426.8) Bq/kg, respectively.

The people typically spend most of their time at home and schools and also it workplaces for teachers and administrators and service staff, who might spend even more time than children in school buildings. In view of this, indoor radon concentration has been carried out in selected residential and schools located in Mandya, Karnataka, using solid-state nuclear track detector technique. Annual mean values of²²²Rn in selected schools and houses were found to be 17.4 and 23.3 Bq/m³, respectively. The data distribution was discussed using lognormal probability plots. The doses to different organs and tissues were calculated using the ICRP model of the respiratory tract, and intercomparison of risk is discussed. It can be seen that the larger fraction of the dose is delivered to the lungs (69%) and extrathoracic region (31%) of the body.

An assessment of radioactivity concentration of different types of houses was conducted at 437 houses of Imphal City, Manipur, India. The average annual effective doses of gamma radiation level in indoor and outdoor were determined as 1.22 ± 0.09 (range: 0.79–1.41) mSvy^-1 and 0.79 ± 0.08 (range: 0.57–1.07) mSvy^-1 for reinforced cement concrete houses, followed by 1.06 ± 0.08 (range: 0.84–1.27) mSvy^-1 and 0.78 ± 0.08 (range: 0.59–0.94) mSvy^-1 for Assam-typed (AT) brick houses, 0.85 ± 0.08 (range: 0.63–1.28) mSvy^-1 and 0.76 ± 0.08 (range: 0.52-1.01) mSvy^-1 for AT mud houses, 0.77 ± 0.08 (range: 0.58–0.96) mSvy^-1 and 0.73 ± 0.07 (range: 0.65–0.85) mSvy^-1 for AT katcha houses, and 1.04 ± 0.07 (range: 0.88–1.22) mSvy^-1 and 0.73 ± 0.07 (range: 0.65–0.84) mSvy^-1 for adobe laid earthen houses, respectively. Moreover, the annual effective dose conceived from building materials was recorded as 1.8 mSvy^-1 from sand, 1.5 mSvy^-1 from brick, and 1.0 mSvy^-1 from Portland cement. The worldwide average indoor dose limit of radon conceiving and its decay product by inhalation is 1.15 mSvy^-1 prescribed by the UNSCEAR (2000).

Radon concentration in a room can be predicted from accurate knowledge of exhalation rates from six surfaces of the room. Walls of a room occupy the maximum surface area of the room. Hence, the contribution of walls to indoor radon concentration is significant. Since the direct measurement of exhalation rate from the walls is difficult, generally, the typical building materials used for wall construction are analyzed for exhalation rates, and from these measurements, exhalation rates from walls are estimated. In the present work, an attempt has been made to estimate the exhalation rate from a wall during various stages of construction by measuring exhalation rates from various building materials and to study the effect of various layers of coatings on exhalation rates. This analysis can help in selecting right materials for construction to mitigate the indoor radon concentrations.

Radiation exposure in humans can emanate from natural radionuclides through uranium and thorium decay series as well as⁴⁰K due to emitted ionising radiations. It is important to estimate the exposure of humans to the diverse sources of radiation. In this study, the activity concentrations of natural radionuclides²³⁸U and²³²Th in granitic rock samples from uranium mine sites in parts of Northern Nigeria were measured, by inductively coupled plasma-mass spectrometry. The highest values of²³⁸U and²³²Th concentrations (924.56 ± 17.13 and 21.96 ± 1.28 Bq/kg, respectively) were observed at Mika-I and Riruwai. Furthermore, the radiological exposure parameters (i.e., absorbed dose rate in air [D], annual effective dose [external], radium equivalent activity (Ra_eq), external exposure index (H_ex), internal exposure index (H_in), and representative level index (I_γand I_α) were estimated and compared to the international recommended values. In terms of terrestrial gamma radiation from granitic rock within the study area, it does not pose any significant radiation exposure to the workers and dwellers.

The heavy metal accumulation study on bed sediments of Kodangari stream situated in Enmakaje panchayath of Kasaragod district, Kerala, has been carried out. A total of 20 sediment samples along the stream were collected and analyzed for the concentration of heavy metals, namely manganese (Mn), zinc (Zn), copper (Cu), and iron (Fe), using a flame atomic absorption spectrometer. The observed concentration of Mn varies in the range of 0.14–32.80 ppm, the concentration of Zn varies in the range of 0.15–10.80 ppm, the concentration of Cu varies in the range of 1.80–12.20 ppm, and the concentration of Fe varies in the range of 19.12–378 ppm. The physicochemical parameters, namely pH, moisture content, organic matter content, and electrical conductivity, associated with the samples were also measured and correlated with the concentration of heavy metals. There exists a good correlation between the concentration of heavy metals and various physicochemical parameters. The results obtained are presented and discussed in detail in the manuscript.

In the present study, an attempt has been made to measure the radionuclide contents in soil samples from the region around coal-based thermal power plant (TPP) in Tarn Taran district of Punjab state in India and to assess the impact of coal-based TPP on the radionuclide distribution in surrounding areas. For this purpose, soil samples collected from the region, coal samples, and fly-ash samples collected from the plant were analyzed using the gamma spectrometry technique employing thallium-activated sodium iodide detector. The activity concentration of radionuclides was observed to be higher for the samples collected from the locations nearer to the power plant and decreased as the distance from power plant increased indicating an increase in soil radioactivity due to TPP.